List<T>.TrueForAll(Predicate<T>) メソッド

定義

List<T> 内のすべての要素が、指定した述語によって定義される条件に一致するかどうかを調べます。Determines whether every element in the List<T> matches the conditions defined by the specified predicate.

public:
 bool TrueForAll(Predicate<T> ^ match);
public bool TrueForAll (Predicate<T> match);
member this.TrueForAll : Predicate<'T> -> bool
Public Function TrueForAll (match As Predicate(Of T)) As Boolean

パラメーター

match
Predicate<T>

要素の条件を定義する Predicate<T> デリゲート。The Predicate<T> delegate that defines the conditions to check against the elements.

戻り値

List<T> 内のすべての要素が、指定した述語によって定義される条件に一致する場合は true。それ以外の場合は falsetrue if every element in the List<T> matches the conditions defined by the specified predicate; otherwise, false. リストに要素がない場合、戻り値は true です。If the list has no elements, the return value is true.

例外

matchnullです。match is null.

次の例は、TrueForAll メソッドと、Predicate<T> 汎用デリゲートを使用する他のいくつかのメソッドを示しています。The following example demonstrates the TrueForAll method and several other methods that use Predicate<T> generic delegate.

文字列の List<T> が作成されます。これには8つの恐竜の名前が含まれ、そのうちの2つ (位置1と 5) の末尾が "saurus" になります。A List<T> of strings is created, containing 8 dinosaur names, two of which (at positions 1 and 5) end with "saurus". また、この例では、文字列パラメーターを受け取り、入力文字列が "saurus" で終わるかどうかを示すブール値を返す、EndsWithSaurusという名前の検索述語メソッドを定義しています。The example also defines a search predicate method named EndsWithSaurus, which accepts a string parameter and returns a Boolean value indicating whether the input string ends in "saurus".

TrueForAll メソッドは、最初からリストを走査し、各要素を順番に EndsWithSaurus メソッドに渡します。The TrueForAll method traverses the list from the beginning, passing each element in turn to the EndsWithSaurus method. EndsWithSaurus メソッドが falseを返すと、検索は停止します。The search stops when the EndsWithSaurus method returns false.

注意

およびC# Visual Basic では、Predicate<string>デリゲート (Visual Basic でPredicate(Of String)) を明示的に作成する必要はありません。In C# and Visual Basic, it is not necessary to create the Predicate<string> delegate (Predicate(Of String) in Visual Basic) explicitly. これらの言語は、コンテキストから正しいデリゲートを推測し、自動的に作成します。These languages infer the correct delegate from context and create it automatically.

using namespace System;
using namespace System::Collections::Generic;

// Search predicate returns true if a string ends in "saurus".
bool EndsWithSaurus(String^ s)
{
    return s->ToLower()->EndsWith("saurus");
};

void main()
{
    List<String^>^ dinosaurs = gcnew List<String^>();

    dinosaurs->Add("Compsognathus");
    dinosaurs->Add("Amargasaurus");
    dinosaurs->Add("Oviraptor");
    dinosaurs->Add("Velociraptor");
    dinosaurs->Add("Deinonychus");
    dinosaurs->Add("Dilophosaurus");
    dinosaurs->Add("Gallimimus");
    dinosaurs->Add("Triceratops");

    Console::WriteLine();
    for each(String^ dinosaur in dinosaurs )
    {
        Console::WriteLine(dinosaur);
    }

    Console::WriteLine("\nTrueForAll(EndsWithSaurus): {0}",
        dinosaurs->TrueForAll(gcnew Predicate<String^>(EndsWithSaurus)));

    Console::WriteLine("\nFind(EndsWithSaurus): {0}", 
        dinosaurs->Find(gcnew Predicate<String^>(EndsWithSaurus)));

    Console::WriteLine("\nFindLast(EndsWithSaurus): {0}",
        dinosaurs->FindLast(gcnew Predicate<String^>(EndsWithSaurus)));

    Console::WriteLine("\nFindAll(EndsWithSaurus):");
    List<String^>^ sublist = 
        dinosaurs->FindAll(gcnew Predicate<String^>(EndsWithSaurus));

    for each(String^ dinosaur in sublist)
    {
        Console::WriteLine(dinosaur);
    }

    Console::WriteLine(
        "\n{0} elements removed by RemoveAll(EndsWithSaurus).", 
        dinosaurs->RemoveAll(gcnew Predicate<String^>(EndsWithSaurus)));

    Console::WriteLine("\nList now contains:");
    for each(String^ dinosaur in dinosaurs)
    {
        Console::WriteLine(dinosaur);
    }

    Console::WriteLine("\nExists(EndsWithSaurus): {0}", 
        dinosaurs->Exists(gcnew Predicate<String^>(EndsWithSaurus)));
}

/* This code example produces the following output:

Compsognathus
Amargasaurus
Oviraptor
Velociraptor
Deinonychus
Dilophosaurus
Gallimimus
Triceratops

TrueForAll(EndsWithSaurus): False

Find(EndsWithSaurus): Amargasaurus

FindLast(EndsWithSaurus): Dilophosaurus

FindAll(EndsWithSaurus):
Amargasaurus
Dilophosaurus

2 elements removed by RemoveAll(EndsWithSaurus).

List now contains:
Compsognathus
Oviraptor
Velociraptor
Deinonychus
Gallimimus
Triceratops

Exists(EndsWithSaurus): False
 */
using System;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        List<string> dinosaurs = new List<string>();

        dinosaurs.Add("Compsognathus");
        dinosaurs.Add("Amargasaurus");
        dinosaurs.Add("Oviraptor");
        dinosaurs.Add("Velociraptor");
        dinosaurs.Add("Deinonychus");
        dinosaurs.Add("Dilophosaurus");
        dinosaurs.Add("Gallimimus");
        dinosaurs.Add("Triceratops");

        Console.WriteLine();
        foreach(string dinosaur in dinosaurs)
        {
            Console.WriteLine(dinosaur);
        }

        Console.WriteLine("\nTrueForAll(EndsWithSaurus): {0}",
            dinosaurs.TrueForAll(EndsWithSaurus));

        Console.WriteLine("\nFind(EndsWithSaurus): {0}", 
            dinosaurs.Find(EndsWithSaurus));

        Console.WriteLine("\nFindLast(EndsWithSaurus): {0}",
            dinosaurs.FindLast(EndsWithSaurus));

        Console.WriteLine("\nFindAll(EndsWithSaurus):");
        List<string> sublist = dinosaurs.FindAll(EndsWithSaurus);

        foreach(string dinosaur in sublist)
        {
            Console.WriteLine(dinosaur);
        }

        Console.WriteLine(
            "\n{0} elements removed by RemoveAll(EndsWithSaurus).", 
            dinosaurs.RemoveAll(EndsWithSaurus));

        Console.WriteLine("\nList now contains:");
        foreach(string dinosaur in dinosaurs)
        {
            Console.WriteLine(dinosaur);
        }

        Console.WriteLine("\nExists(EndsWithSaurus): {0}", 
            dinosaurs.Exists(EndsWithSaurus));
    }

    // Search predicate returns true if a string ends in "saurus".
    private static bool EndsWithSaurus(String s)
    {
        return s.ToLower().EndsWith("saurus");
    }
}

/* This code example produces the following output:

Compsognathus
Amargasaurus
Oviraptor
Velociraptor
Deinonychus
Dilophosaurus
Gallimimus
Triceratops

TrueForAll(EndsWithSaurus): False

Find(EndsWithSaurus): Amargasaurus

FindLast(EndsWithSaurus): Dilophosaurus

FindAll(EndsWithSaurus):
Amargasaurus
Dilophosaurus

2 elements removed by RemoveAll(EndsWithSaurus).

List now contains:
Compsognathus
Oviraptor
Velociraptor
Deinonychus
Gallimimus
Triceratops

Exists(EndsWithSaurus): False
 */
Imports System.Collections.Generic

Public Class Example

    Public Shared Sub Main()

        Dim dinosaurs As New List(Of String)

        dinosaurs.Add("Compsognathus")
        dinosaurs.Add("Amargasaurus")
        dinosaurs.Add("Oviraptor")
        dinosaurs.Add("Velociraptor")
        dinosaurs.Add("Deinonychus")
        dinosaurs.Add("Dilophosaurus")
        dinosaurs.Add("Gallimimus")
        dinosaurs.Add("Triceratops")

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & _
            "TrueForAll(AddressOf EndsWithSaurus: {0}", _
            dinosaurs.TrueForAll(AddressOf EndsWithSaurus))

        Console.WriteLine(vbLf & _
            "Find(AddressOf EndsWithSaurus): {0}", _
            dinosaurs.Find(AddressOf EndsWithSaurus))

        Console.WriteLine(vbLf & _
            "FindLast(AddressOf EndsWithSaurus): {0}", _
            dinosaurs.FindLast(AddressOf EndsWithSaurus))

        Console.WriteLine(vbLf & _
            "FindAll(AddressOf EndsWithSaurus):")
        Dim sublist As List(Of String) = _
            dinosaurs.FindAll(AddressOf EndsWithSaurus)

        For Each dinosaur As String In sublist
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & _
            "{0} elements removed by RemoveAll(AddressOf EndsWithSaurus).", _
            dinosaurs.RemoveAll(AddressOf EndsWithSaurus))

        Console.WriteLine(vbLf & "List now contains:")
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & _
            "Exists(AddressOf EndsWithSaurus): {0}", _
            dinosaurs.Exists(AddressOf EndsWithSaurus))
        
    End Sub

    ' Search predicate returns true if a string ends in "saurus".
    Private Shared Function EndsWithSaurus(ByVal s As String) _
        As Boolean

        Return s.ToLower().EndsWith("saurus")
    End Function
End Class

' This code example produces the following output:
'
'Compsognathus
'Amargasaurus
'Oviraptor
'Velociraptor
'Deinonychus
'Dilophosaurus
'Gallimimus
'Triceratops
'
'TrueForAll(AddressOf EndsWithSaurus: False
'
'Find(AddressOf EndsWithSaurus): Amargasaurus
'
'FindLast(AddressOf EndsWithSaurus): Dilophosaurus
'
'FindAll(AddressOf EndsWithSaurus):
'Amargasaurus
'Dilophosaurus
'
'2 elements removed by RemoveAll(AddressOf EndsWithSaurus).
'
'List now contains:
'Compsognathus
'Oviraptor
'Velociraptor
'Deinonychus
'Gallimimus
'Triceratops
'
'Exists(AddressOf EndsWithSaurus): False

注釈

Predicate<T> は、渡されたオブジェクトがデリゲートで定義されている条件に一致する場合に true を返すメソッドのデリゲートです。The Predicate<T> is a delegate to a method that returns true if the object passed to it matches the conditions defined in the delegate. 現在の List<T> の要素は、個別に Predicate<T> デリゲートに渡され、デリゲートが任意の要素に対して false を返すと処理が停止されます。The elements of the current List<T> are individually passed to the Predicate<T> delegate, and processing is stopped when the delegate returns false for any element. 要素は順番に処理され、すべての呼び出しが1つのスレッドで行われます。The elements are processed in order, and all calls are made on a single thread.

このメソッドは O (n) 操作です。ここで、 nCountです。This method is an O(n) operation, where n is Count.

適用対象

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